A 58-year-old man with a long-standing diagnosis of schizoaffective disorder is brought to the emergency department for acute change in mental status. He lives in a group home and was assigned a new roommate 2 weeks earlier; the staff reports that the patient has become increasingly paranoid and agitated since then. His antipsychotic medication was changed from quetiapine to fluphenazine last week, but his behavior did not improve despite increasing dosages. The patient's other medications include a selective serotonin reuptake inhibitor and acetaminophen. Over the past several days, he developed a fever and has become increasingly confused.
On arrival, the patient's temperature is 40.0 C (104 F) , blood pressure is 170/110 mm Hg, pulse is 115/min, and respirations are 22/min. The patient is diaphoretic, and examination shows diffuse rigidity. There is no evidence of infection. He is disoriented to place and time.
Laboratory evaluation shows leukocytes 11,500/mm³ and creatine kinase 3,500 U/L. Urinalysis is unremarkable.
In addition to supportive measures, which of the following is the most appropriate initial step in management of this patient?

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11ec193a_9697_7b19_853d_f1dac90d8f3b_MD0002_00 This patient's development of high fever, confusion, autonomic instability, generalized muscular rigidity, and elevated creatine kinase shortly after starting the first-generation antipsychotic fluphenazine is consistent with neuroleptic malignant syndrome (NMS). NMS is a rare but potentially lethal adverse reaction to antipsychotic medications and is characterized by severe hyperthermia, muscular (lead-pipe) rigidity, altered sensorium, and autonomic instability. An elevated creatine kinase level due to muscle breakdown and leukocytosis is a common finding. The single most important intervention in NMS is prompt discontinuation of the causative agent. Transfer to the intensive care unit for supportive care (eg, aggressive cooling, antipyretics, fluid and electrolyte repletion, blood pressure control) may be necessary. Signs and symptoms of NMS should improve after the antipsychotic is stopped. The use of dantrolene, a direct-acting muscle relaxant, is not well supported and should be considered only when patients do not respond to supportive care and withdrawal of medication (Choice C). (Choice A) Benztropine is used to treat antipsychotic-induced extrapyramidal symptoms, such as acute dystonic reactions and parkinsonism. Anticholinergic agents are ineffective in the treatment of NMS and may worsen hyperthermia. (Choices B and E) Administering cyproheptadine, which has anti-serotonergic properties, and discontinuing the selective serotonin reuptake inhibitor are treatments for serotonin syndrome. Serotonin syndrome also presents with autonomic instability and altered mental status, but it is characterized by neuromuscular irritability and gastrointestinal symptoms rather than diffuse rigidity. It is less likely in this patient who has had a recent increase in his antipsychotic dose and has diffuse rigidity rather than hyperreflexia and myoclonus. Educational objective: Neuroleptic malignant syndrome is characterized by mental status change, muscle rigidity, high fever, and autonomic instability. Management involves prompt discontinuation of the causative agent and aggressive supportive measures. __________ References: Neuroleptic malignant syndrome: an easily overlooked neurologic emergency. (http://www.ncbi.nlm.nih.gov/pubmed/28144147) Neuroleptic malignant syndrome: a review for neurohospitalists. (http://www.ncbi.nlm.nih.gov/pubmed/23983836)

A 58-Year-Old Man with a Long-Standing Diagnosis of Schizoaffective Disorder